[systemd-devel] [ANNOUNCE] systemd 219

[Lennart Poettering]

On Wed, 03.05.17 22:57, Florian Kerle (flo.kerle at gmx.at) wrote:

> Hi Lennart,
> 
> it's correct, that checksums are not suitable to recover a file;
> BUT when using btrfs RAID, checksums are used to determine which copy of the file is malformed.
> (and restore it, if any redundant OK copy exists)
> 
> Using FS_NOCOW on journal files does prevent btrfs from restoring the journal, even if a sane copy would exist.
> (i.e. hardware / drive failure.)
> That probably means losing important data.
> 
> While this IMHO seems like a temporary workaround until btrfs autodefrag (on a per file basis) exist,
> I'd rather make this configurable and surely not the default!
> 
> Do you have any further info or opinion on this?

As discussed already, there's a very easy way to disable this:

ln -s /dev/null /etc/tmpfiles.d/journal-nocow.conf

Lennart

-- 
Lennart Poettering, Red Hat